From nobody Fri Apr 19 10:42:17 2024 Delivered-To: importer@patchew.org Received-SPF: pass (zohomail.com: domain of lists.xenproject.org designates 192.237.175.120 as permitted sender) client-ip=192.237.175.120; envelope-from=xen-devel-bounces@lists.xenproject.org; helo=lists.xenproject.org; Authentication-Results: mx.zohomail.com; dkim=pass; spf=pass (zohomail.com: domain of lists.xenproject.org designates 192.237.175.120 as permitted sender) smtp.mailfrom=xen-devel-bounces@lists.xenproject.org; dmarc=pass(p=none dis=none) header.from=kernel.org ARC-Seal: i=1; a=rsa-sha256; t=1602110336; cv=none; d=zohomail.com; s=zohoarc; b=Fd+9f1huxuNk+66losRL+QVuzaJ2ciewfl6+s+8nWufhuRc2YduczMBzLwBlP/aAARJZXUgR5IRNZiU2dAxMdLazGdVgvKM4r00yM8VEGye/zDXKYmKfZhJdfbXDTko4D7KFpep2DCbQAHmV4Wg69lamP8ozh1N2dTTB72PdrdQ= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zohomail.com; s=zohoarc; t=1602110336; h=Cc:Date:From:List-Subscribe:List-Post:List-Id:List-Help:List-Unsubscribe:Message-ID:Sender:Subject:To; bh=Rb2+8UiMEJLe/uSG2J5oRn9T4klcaJxJjpe4+mY5FK8=; b=iavU3SZrz4JPzIdIcrK19lJ7M0NmHkt6z0fZON6ebK2uyf/y0YbERXFe8qCqBnLDb51zP61wB3WVYet4uNpNw8mhxSZ1EYkmkiVLALpLIJPR4OwlaoEvYOpiv2HVk8cq9U31h7FzN0AcRBUeMkwLjwfe04m1TPqYE6o9S5+rQlE= ARC-Authentication-Results: i=1; mx.zohomail.com; dkim=pass; spf=pass (zohomail.com: domain of lists.xenproject.org designates 192.237.175.120 as permitted sender) smtp.mailfrom=xen-devel-bounces@lists.xenproject.org; dmarc=pass header.from= (p=none dis=none) header.from= Return-Path: Received: from lists.xenproject.org (lists.xenproject.org [192.237.175.120]) by mx.zohomail.com with SMTPS id 1602110336383632.8123458876125; Wed, 7 Oct 2020 15:38:56 -0700 (PDT) Received: from list by lists.xenproject.org with outflank-mailman.3824.11411 (Exim 4.92) (envelope-from ) id 1kQI4g-0002MM-CX; Wed, 07 Oct 2020 22:38:18 +0000 Received: by outflank-mailman (output) from mailman id 3824.11411; Wed, 07 Oct 2020 22:38:18 +0000 Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1kQI4g-0002MF-9X; Wed, 07 Oct 2020 22:38:18 +0000 Received: by outflank-mailman (input) for mailman id 3824; Wed, 07 Oct 2020 22:38:17 +0000 Received: from us1-rack-iad1.inumbo.com ([172.99.69.81]) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1kQI4f-0002MA-37 for xen-devel@lists.xenproject.org; Wed, 07 Oct 2020 22:38:17 +0000 Received: from mail.kernel.org (unknown [198.145.29.99]) by us1-rack-iad1.inumbo.com (Halon) with ESMTPS id 3a5a90dd-7fc0-494e-8f89-e3077fbec196; Wed, 07 Oct 2020 22:38:16 +0000 (UTC) Received: from sstabellini-ThinkPad-T480s.hsd1.ca.comcast.net (c-24-130-65-46.hsd1.ca.comcast.net [24.130.65.46]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 9C81A2083B; Wed, 7 Oct 2020 22:38:15 +0000 (UTC) Received: from us1-rack-iad1.inumbo.com ([172.99.69.81]) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1kQI4f-0002MA-37 for xen-devel@lists.xenproject.org; Wed, 07 Oct 2020 22:38:17 +0000 Received: from mail.kernel.org (unknown [198.145.29.99]) by us1-rack-iad1.inumbo.com (Halon) with ESMTPS id 3a5a90dd-7fc0-494e-8f89-e3077fbec196; Wed, 07 Oct 2020 22:38:16 +0000 (UTC) Received: from sstabellini-ThinkPad-T480s.hsd1.ca.comcast.net (c-24-130-65-46.hsd1.ca.comcast.net [24.130.65.46]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 9C81A2083B; Wed, 7 Oct 2020 22:38:15 +0000 (UTC) X-Outflank-Mailman: Message body and most headers restored to incoming version X-BeenThere: xen-devel@lists.xenproject.org List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Errors-To: xen-devel-bounces@lists.xenproject.org Precedence: list Sender: "Xen-devel" X-Inumbo-ID: 3a5a90dd-7fc0-494e-8f89-e3077fbec196 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1602110295; bh=l4K4T8fo0+ur1aHgV4iAACL0DIXhCf13YMCySooTSfU=; h=From:To:Cc:Subject:Date:From; b=KPzCRZISJ89qN6/XajpmMZeVn7i2WBUxK1Dc6hmaq6OVONbmAUeqW0NvE3+PtuE3k X1jgKugLQYslqshZPX7EGtjrWiH+lPnMdhQevscbQwdA2wh/dJPCsJFap887rfueg9 LBkwFIZAd2y+bseiVqBkTGhLeVl13JkfxOYpULd4= From: Stefano Stabellini To: xen-devel@lists.xenproject.org Cc: julien@xen.org, sstabellini@kernel.org, Stefano Stabellini , roman@zededa.com Subject: [PATCH v3] xen/rpi4: implement watchdog-based reset Date: Wed, 7 Oct 2020 15:38:13 -0700 Message-Id: <20201007223813.1638-1-sstabellini@kernel.org> X-Mailer: git-send-email 2.17.1 X-ZohoMail-DKIM: pass (identity @kernel.org) Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" The preferred method to reboot RPi4 is PSCI. If it is not available, touching the watchdog is required to be able to reboot the board. The implementation is based on drivers/watchdog/bcm2835_wdt.c:__bcm2835_restart in Linux v5.9-rc7. Signed-off-by: Stefano Stabellini Acked-by: Julien Grall CC: roman@zededa.com Reviewed-by: Bertrand Marquis Tested-by: Roman Shaposhnik --- Changes in v3: - fix typo in commit message - dprintk -> printk --- xen/arch/arm/platforms/brcm-raspberry-pi.c | 61 ++++++++++++++++++++++ 1 file changed, 61 insertions(+) diff --git a/xen/arch/arm/platforms/brcm-raspberry-pi.c b/xen/arch/arm/plat= forms/brcm-raspberry-pi.c index f5ae58a7d5..811b40b1a6 100644 --- a/xen/arch/arm/platforms/brcm-raspberry-pi.c +++ b/xen/arch/arm/platforms/brcm-raspberry-pi.c @@ -17,6 +17,10 @@ * GNU General Public License for more details. */ =20 +#include +#include +#include +#include #include =20 static const char *const rpi4_dt_compat[] __initconst =3D @@ -37,12 +41,69 @@ static const struct dt_device_match rpi4_blacklist_dev[= ] __initconst =3D * The aux peripheral also shares a page with the aux UART. */ DT_MATCH_COMPATIBLE("brcm,bcm2835-aux"), + /* Special device used for rebooting */ + DT_MATCH_COMPATIBLE("brcm,bcm2835-pm"), { /* sentinel */ }, }; =20 + +#define PM_PASSWORD 0x5a000000 +#define PM_RSTC 0x1c +#define PM_WDOG 0x24 +#define PM_RSTC_WRCFG_FULL_RESET 0x00000020 +#define PM_RSTC_WRCFG_CLR 0xffffffcf + +static void __iomem *rpi4_map_watchdog(void) +{ + void __iomem *base; + struct dt_device_node *node; + paddr_t start, len; + int ret; + + node =3D dt_find_compatible_node(NULL, NULL, "brcm,bcm2835-pm"); + if ( !node ) + return NULL; + + ret =3D dt_device_get_address(node, 0, &start, &len); + if ( ret ) + { + printk("Cannot read watchdog register address\n"); + return NULL; + } + + base =3D ioremap_nocache(start & PAGE_MASK, PAGE_SIZE); + if ( !base ) + { + printk("Unable to map watchdog register!\n"); + return NULL; + } + + return base; +} + +static void rpi4_reset(void) +{ + uint32_t val; + void __iomem *base =3D rpi4_map_watchdog(); + + if ( !base ) + return; + + /* use a timeout of 10 ticks (~150us) */ + writel(10 | PM_PASSWORD, base + PM_WDOG); + val =3D readl(base + PM_RSTC); + val &=3D PM_RSTC_WRCFG_CLR; + val |=3D PM_PASSWORD | PM_RSTC_WRCFG_FULL_RESET; + writel(val, base + PM_RSTC); + + /* No sleeping, possibly atomic. */ + mdelay(1); +} + PLATFORM_START(rpi4, "Raspberry Pi 4") .compatible =3D rpi4_dt_compat, .blacklist_dev =3D rpi4_blacklist_dev, + .reset =3D rpi4_reset, .dma_bitsize =3D 30, PLATFORM_END =20 --=20 2.17.1